title: Dental pulp stem cells from traumatically exposed pulps exhibited an enhanced osteogenic potential and weakened odontogenic capacity.
abstract: OBJECTIVE
  Traumatic pulp exposure can bring about some permanent damages to tooth tissues including dental pulps. This study was designed to evaluate the effects of traumatic pulp exposure on the osteo/odontogenic capacity of dental pulp stem cells (DPSCs).
  
  
  METHODS
  Rat incisors were artificially fractured and dental pulps were exposed to the oral environment for 48 h. Then, multi-colony-derived DPSCs from the injured pulps (iDPSCs) were isolated. Their osteo/odontogenic differentiation and the involvement of NF-κB pathway were subsequently investigated.
  
  
  RESULTS
  iDPSCs presented a lower proliferative capacity than normal DPSCs (nDPSCs), as indicated by MTT and FCM assay. ALP levels in iDPSCs were significantly higher (P<0.01) than those in nDPSCs. Alizarin red staining revealed that iDPSCs exhibited an increased capacity of calcium deposition. Moreover, iDPSCs expressed stronger osteogenic markers (Runx2/RUNX2 and Ocn/OCN) and less odontogenic gene/protein (Dspp/DSP) than nDPSCs in vitro. In vivo transplantation showed that nDPSCs implants generated the typical dentine-pulp complex while all iDPSCs pellets formed the osteodentin-like tissues which were immunopositive for OCN. Mechanistically, iDPSCs expressed the higher levels of cytoplasmic phosphorylated IκBα/P65 and nuclear P65 than nDPSCs, indicating an active cellular NF-κB pathway in iDPSCs. After the inhibition of NF-κB pathway, the osteogenic potential in iDPSCs was significantly down-regulated while odontogenic differentiation was up-regulated, as indicated by the decreased Alp/Runx2/Ocn and uprised Dspp expression.
  
  
  CONCLUSIONS
  Pulp exposure for 48 h decreased the odontogenic capacity and enhanced the osteogenic potential of DPSCs via the NF-κB signalling pathway.
authors.affiliation: Institute of Stomatology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China; Endodontic Department, The Affiliated Stomatological Hospital of Soochow University, Suzhou Stomatological Hospital, 1505 Renmin Road, Suzhou, Jiangsu 215005, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Yan
authors.forename: Zhanwei
authors.initials: Z
authors.lastname: Wang
authors.forename: Jintao
authors.initials: J
authors.lastname: Wu
authors.forename: Zilu
authors.initials: Z
authors.lastname: Wang
authors.forename: Yangyu
authors.initials: Y
authors.lastname: Zheng
authors.forename: Jinhua
authors.initials: J
authors.lastname: Yu
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism; D003782:Dental Pulp / Q000166:cytology / Q000293:injuries* / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism; D005434:Flow Cytometry; D015870:Gene Expression; D016328:NF-kappa B / Q000378:metabolism*; D009805:Odontogenesis / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012795:Sialoglycoproteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D013778:Tetrazolium Salts; D000099311:Dentin Sialophosphoprotein
chemical_list: D000469:Alkaline Phosphatase; D050659:Core Binding Factor Alpha 1 Subunit; D016326:Extracellular Matrix Proteins; D016328:NF-kappa B; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D013778:Tetrazolium Salts; D000099311:Dentin Sialophosphoprotein; C493717:Runx2 protein, rat
keywords: AGS; ALP; CPC; DMSO; DPSCs; DSP; DSPP; Dental pulp; FBS; FCM; GAPDH; Injury; MM; NF-κB; Nuclear factor kappa B; OCN; Odontoblast; Osteoblast; PI; PVDF; RUNX2; Real-time RT-PCR; Stem cell; absorbable gelatin sponges; alkaline phosphatase; alpha minimum essential medium; cetylpyridinium chloride; dental pulp stem cells; dentin sialophosphoprotein; dentin sialoprotein; dimethyl sulfoxide; fetal bovine serum; flow cytometry; glyceraldehyde-3-phosphate dehydrogenase; mineralization-inducing media; nuclear factor kappa B; osteocalcin; polyvinylidene difluoride; proliferation index; real-time reverse transcription polymerase chain reaction; runt-related transcription factor 2; α-MEM